Mouthpiece facing machine



Dec. 17, 1940. v H. H. CANTERBURY 2,225,154

MOUTHPIECE FACING MACHINE 4 Sheets-Sheet 1 Filed Aug. 13, 1937 I f lu ii W Q islli Harry H Chmerwy Dec. 17, 1940. H. H. CANTERBURY MOUTHPIECE FACING MACHINE Filed Aug. 13, 1937 I I I i m! "II II' War/ H 67:20 zerbu/y 4 Sheets-Sheet 2 Sum/M11 5 Dec. 17, 1940. H. H. CANTERBURY MOUTHPIECE FACING MACHINE Filed Aug. 13, 1957 4 Sheets-Sheet 5 Harry H Qzflzerbagf 1940- H. H. CANTERBURY 2,225,154

MOUTHPIECE FACING MACHINE Filed Aug. 15, 1957 4 Sheets-Sheet 4 Patented Dec. 17, 1940 UNITE s'rarss PATENT OFFICE 12 Claims.

The present invention relates generally to precision facing machines and more particularly to machines for cutting or facing blanks to form mouthpieces for musical instruments such as the saxophone, clarinet, etc. The blanks may be made of any suitable material that is hard enough to take and retain a precise shape and is free from even minute distortion produced by internal strains, temperature changes, or hygroscopic tendencies. Various materials used have been wood, hard rubber, glass, and other manufac tured products such as certain synthetic resins, a typical one of the latter being the product known to the trade as Catalin.

Mouthpieces have formerly been made by hand methods as a general rule because no mechanical means has proved especially advantageous; The manual product is fundamentally objectionable because of the inaccuracy of'the curve to the face and rails over which the reed lies. Along with the general objections to an individual piece of low quality there is the objection of non-uniformity in the product as 'a whole, because each piece, being made individually, has its own unique characteristics and irregularities. The obvious consequence is that it is not possible to reproduce exactly, in quantity or at a reasonable cost, a mouthpiece having especially'desirable playing characteristics. While the price of the ordinary hand-cut piece has not been excessive, yet the production of extra fine pieces cannot be done by hand methods at a commercially satisfactory price.

The usual mouthpiece is generally'circular in.

cross section, tapering toward one end to form a portion of which is flat and the remainder of which is curved longitudinally toward the outer or beak end of the mouthpiece. The face becomes only a pair of narrow side rails where the throat of the piece opens to the face at the beak end. The playing reed lies over the mouthpiece face and is clamped toward its inner end to the fiat portion ofthe face, being free at its outer end to vibrate. Production of musical tones occurs by alternate stoppage and entrance of air through the space between the reed and'the tip of the mouthpiece into the throat of the piece. The reed vibrates periodically in synchronism with the natural harmonic resonance of the body of air partially enclosed within the tube of the instrument, the elastic ty of the reed assisting in the prolongation of the vibration. Since the playing quality of the mouthpiece depends on the completeness of the air seal, the face and rails need to conform accurately to the curvature assumed by the reed as it is deflected by the force of alternate rarefactions and condensations of air within the tube ofthe instrument.

The reed is clamped at its thicker portion, leaving the remainder, normally about one-half; its length, free to vibrate. This free end of the reed is thinned toward the outer end in a-uniform manner, and may be likened to a cantilever beam of outwardly decreasing depth; and when the reed is bent by air pressure over its surface, it assumes a regular curvegenerally similar to that taken by such a cantilever member under uniform loading. The outer end of the face on-the mouthpiece is therefore curvedlongitudinally to the same curve assumed by the lower face of the reed.

Themouthpiece is most easily faced from a template, but if. the template curve is identical in size with the mouthpiece curve, the desired high degree ofaccuracy of the latter is difficult to secure because it is difficult to make'thetemplate of sufiicient accuracy. In addition to'this, the mechanical linkage for reproducing the curve introduces errors of its own, with the result that '25 the reproduced curve is even less accurate than the originaltemplate. If the template is enlarged in all dimensions, the mechanism required Itis thus a general object of my invention to provide meansfor making mouthpieces with extreme accuracy. The accuracymust-be of two kinds, for not only must the face betransversely flat and present a precise, even longitudinally curve free from minor irregularities and merging smoothly into the longitudinallyv flat portion of the face, but the shape of the curve must conform precisely to a predetermined shape. I I

It is also an object to secure uniformity of product so that a mouthpiece of desirable characteristics can be readily duplicated, not only individually but in quantity. f

Subsidiary to the aims of accuracy and uniformity but nevertheless important, is also the object of providing means for cheaply facing mouthpiece blanks on a production basis.

Another object of my invention is to provide a machine in which a standard template is used to guide the cutting tool and in which the dimensions of the face made by the tool are reduced along one axis from the dimensions of the template, but along the other axis the template and face dimensions are the same.

An additional object is to provide apparatus in which the ratio of reduction of dimensions from the template to the cut face can be varied easily and quickly to produce limitless variations in the curvature to the face within the range obtainable from a single template.

These objects are attained in a preferred form of machine constructed according to my invention by providing a cutting tool, the movement of which can be accurately controlled, and support means for holding one or a number of blanks in postiion to be moved past the tool by rotation of the supporting means. The relative movement of tool and blank removes material from the blank to form thereon the desired face. A template and follower means is provided by which one component of the tool motion is determined, and a member interconnects the follower and tool to impart the desired movement of the tool. The interconnecting member is preferably movable longitudinally, carrying the tool and follower with it, thus moving the follower over a template surface curved to produce the desired curved face on the blank. The interconnecting member is likewise pivoted at some point with the cutting tool placed a shorter distance from the pivot than the template is from the pivot. Although the invention-includes placing the tool and follower on opposite sides of the pivot, it is preferred to place them both on the same side because of simplification of construction and because the paths of the tool and follower then both curve in the same direction. This longitudinal movement of the interconnecting member is one component of the movement of both follower and tool and is equal for both these elements. The curvature-'of'the template surface produces a component of follower movement at right angles to the first component and, since the interconnecting member also swings about its pivotal mount, the corresponding component of the tool movement is determined by the ratio of the distances of the follower and tool from the pivot. Reference should also be made to my co-pending application entitled Work holder for facing machines, Ser. No. 244,411, filed November '7, 1938, wherein I claim various aspects of means herein shown and described for holding the mouthpiece blanks in position during the facing operation.

How the above, and other objects and advantages of my invention which will become apparent are attained, will be better understood from the following description of a present preferred embodiment of my invention and the annexed drawings, in which:

Fig. 1 is a plan view of a machine for facing mouth-pieces for musical instruments constructed in accord with my invention, a portion of the blank-holding drum being broken away;

Fig. 2 is aside elevation of the mouthpiece facing machine with a portion broken away to show some parts in section.

Fig. 3 is a vertical median section on line 33 of Fig. 2;

Fig. 4 is a vertical section on line 4--4 of Fig. 2 of the tool. holder and'support arm;

Fig. 5 is a vertical section on line 5--5 of Fig. 2 showing the template and follower means in elevation;

Fig. 6 is a fragmentary section on line fi-G of Fig. 3;

Fig. '7 is a fragmentary section on line 'I'! of Fig. 3 showing the opposite side of the cradle support from that shown in Fig. 6;

Fig. 8 is a fragmentary elevation of one end of a mouthpiece blank with the holding cartridge broken away;

Fig. 9 is a vertical section on line 99 of Fig. 8;

Fig. 10 is a fragmentary section as of a portion of Fig. 3 showing a variational form of mounting for the mouthpiece; and

Fig. 11 is a section on line HH of Fig. 2 showing means for measuring vertical movement of the cutting tool.

Referring now more particularly to Figs. 1 and 2, it will be seen that the machine comprises ingeneral a base H] which can be secured to any desired foundation by means of anchor bolts ll. At the left-hand end of base H1 is bridge I2 supporting template M. At the righthand end of base I is mounted a vertical stationary post I upon which rests the supporting assembly generally indicated at It for one end of arm 11. Arm l1 interconnects cutting tool [8 with follower l9 mounted to move over the curved surface of template M in order to control the movement of cutting tool i8, as will be more particularly described. Also mounted at the right-hand end of base I 0 is the assembly for supporting the blanks in. position to engage cutting tool I8, this assembly comprising column 23 rotatably mounted upon the base and concentric with stationary post 15, and, on the upper end of column 20, rotatable drum 2! which is provided with means for supporting the blanks.

Considering the construction now in greater detail, there is shown in Fig. 2 an, opening in the top surface of base It] into which is fitted flanged ring 23 that is bolted to the machine base. Ring 23 provides a footing for stationary vertical post I5 which is threaded at its lower end and received in a central threaded bore in ring 23. Fig. 3 shows the upper end of post l5 to which is attached cap plate 26, preferably circular in form, the two parts being connected by a screw thread. Resting upon cap plate 26 and secured thereto by the counter-sunk screws shown or other means, is base plate 21, likewise circular in outline, which is formed with two upright rail members 28 located one on either side of the center line and parallel to each other, the two members vZBhaving top surfaces lying in the same horizontal plane to form a pair of parallel guide rails that define the longitudinal movement of one end of arm l1.

Placed between the two side rails 28 is cradle 30, the lower portion of which forms a bearing for pivot pin 3|, supporting arm i! as will be later described, the ends of pivot pin 3! being journaled in cradle 39 and held in place by bearing caps 32, one at each end of pin 3|. Each side of the cradle has an upwardly extending side plate 34 that rises above rails 28 and carries short bearing shafts upon which are journaled rollers 35 and 36 resting on rails 23.

The shape and arrangement of rollers. 35 on the left-hand side of cradle 30, as viewed in Fig. 3, is shown in elevation in Fig. 6. The left-hand rail 28 is provided with a longitudinal V-shaped groove 28a, though both rails are preferably alike with a single cylindrical roller 36 that rolls on the flat top surface of rail 28. This construction is preferred because the cradle then rests; upon a three-point support, namely, two rollers 35' and a single roller 36, and adjusts itself accurately to the horizontal plane determined by the two rails 28. Since linear movement is assured by rollers 35 fitting snugly within groove 28a, and

roller 36 simply supports c'r'adle 30 so that it will roll freely, there is nodanger of binding asthe result of inaccuraciesin machining, as might be the case were a V -shaped roller 35 provided to roll within the groove of the right-hand rail28. Pivot pin 3| is mounted with its axis in a horizontal plane parallel to the plane of rails 28, and perpendicular to the direction of movement of cradle30; the movement of the pivot pin axis is limited by the construction described'to a single horizontal plane. v

To the outside face of eachrail 28 is attached an L-shaped cover 38 held in place by screws 39. From the upper horizontal leg of each cover 38 there depends an inner dust plate '40 that extends downwardly inside of side plates 34 to a point just above the horizontal portionof cradle 30. In a like manner, dust plates 4| '(Fig. 6) are supported at each end of each rail 28 from cover 38, sufi'icient clearance beingallowed in all cases .for freemovement of cradle36 with. its side the two strips 43 above rails 28 acting as horizontal guidesthat cooperate with rails 28 toguide the movement of cradle 36. On-the left-hand side plate 34 shown in Fig. 6, there is resiliently mounted a single cylindrical roller .44 which presses against and rolls on the strip 43 immediately'above it. Ontheright-hand side plate 34 shown in Fig. 7, there aretwo cylindrical rollers 45, each roller being journaled on a plate 46 .pivotally mounted by pins 41 to the side plate 34. Spring 48 is attached to plates 46 and draws them together by swinging movement around their-pivotal supports 41, and thus presses rollers 45 into resilient contact. with strip 43 immediately above. By means of this construction, cradle 30 has a resilient, three-point contact with the upper guide provided by'the two strips 43 and the movement of the-"cradle is further restrained to the desired path. Inaccuracies' in manufacture are compensated for by the resilient mounting of the upper rollers which exert a downward pressure that additionally stabilizes the position of the cradle as determined by the three supporting rollers 35 and 36; but the construction is not rigid and will not oppose the guiding effect of rollers 35.

Considering now in detail the means for supporting the blanks in a suitable predetermined position to engage cutting tool l8, it will be seen from Fig. 2 that rotating column 20 is mounted vertically and concentrically of post IS. The lowerend of column 20 is supported on bearing 50 which transmits the load of the'rotating parts to footing ring 23. Excess oil drains from the bearing through drain hole 24. Column 20 is rotated by means of belt passing around pulley 52 attached to the lower end of column 2|], the belt being driven from motor 53 which may be of any suitable type and is preferably provided with aspeed reducer 54 or other similar means for reducing the rotational speed of column 20 to within the desired limits. For the sake of unitary construction and compactness of arrangement, motor 53 is here shown as mounted on base Ill, but it will be realized that other arrangements and placement of the motor may be utilized if desired. Ball bearings 55 are placed at both the upper and lower end of column 20 and fit snugly in the space between the stationary post and the rotating column so that the column turns about the post as an axis. The bearings are held in position by means of suitable flanges 56 secured to post l5.

Rotating drum 2| which carries the blanks is fastened to the upper end of column 20. 2| comprises several parts, including outer shell member 58 formed with a central recess in which the previously described stationary structure forming supporting assembly I6 is placed so that inner shell flange 58a surrounds plates 26 and 21, the shell having a central hub by means of which it is attached to the upper end of column 20. Drum 2| further includes spider 59 which is attached to shell 58 to rotate therewith, the connection between the shell and spider preferably being an adjustable one, for reasons which will be later mentioned, and preferably taking the form of a threaded connection, shown at 60, by which the spider is attached to the inner flange 58a. of the shell. Spider 59 is composed of an inner hub which engages shell flange 58a, and an outer rim 6|, these two parts of the spider being connected by a number of spokes, as shown in Figs. 1 and 3, the open spoke formation being preferred to permit cutting fluid to drain through the spider.

Outer ring 62 forms a portion of drum 2|, and this ring is mounted on the rim 6| of spider 59, the connection between the two members preferably taking the form of the threaded joint 63 extending around the periphery of the spider to provide adjustability between the two members. A number of lock screws 64' are placed at suitable intervals around drum ring. 62 in positions to engage the upper edge of flange 58b of shell 58. When screws 64 are turned down to frictionally engage the shell flange they look the shell and outer ring together in any selected position and also serve to prevent unintended rotation of either or both the spider or ring 62 relative to each other or relative to shell .58. Of course, any other suitable type of locking means may be used.

Spider 59 and ring 62 are each provided with fittings by which the blanks and their holders are mounted radially of drum 2|. Each blank 66 is held in an individual cartridge 61. The cartridge is generally circular in cross-section and tapered longitudinally to approximately the same shape as the outside of the blank 66. Cartridge 61 is open at one end so that the blank can be inserted and moved longitudinally Drum of the cartridge, and is likewise open at the top I throughout its entire length so that the blank is exposed to cutting tool H for the facingoperation. Cartridge El encloses or surrounds at least a portion of the circumference of blank 69, preferably more than half of it so that a firm grip is obtained upon the blank. The cartridge is also open on its under side near the tip end of the blank so that a quick setting, low tensile strength cement, for example pattern makers cement, may be inserted around the tip of the blank and between it and. the cartridge. This cement, shown at $8 in Figs. 8 and 9, fills in all spaces between the blank and the surrounding cartridge and forms a bed of material shaped to fit the blank which firmly holds the blank in place against rotation or any twisting movement in the cartridge. After the blank is completely faced, it is moved longitudinally out of the cartridge, the motion breaking it away from cement 88 which may then be cleaned out of the cartridge in preparation for using the latter again. Fig. 9 is taken near the tip of the mouthpiece and shows the side rails at either side of the throat opening.

The fitting carried on the hub of spider 59 for mounting a blank in place comprises a split plug is threaded into the spider hub and adapted to enter the throat of the blank as shown in Fig. 3. A cylindrical cup H is held between a shoulder on plug Iii and the outer face of the spider hub, cup 1| being of proper size to accommodate the exterior of blank 65. To mount the blank, the throat opening is placed over plug '80 and the blank forced into cup "H compressing spring #2 which presses against the blank. The

outer end of cartridge 61 is then lowered to bring it into alinement with lip 62a on outer ring 62 and the blank with its holder is permitted to move radially outward under pressure exerted by spring '52 until lip 62a seats in horizontal slot E3 of cartridge 61. Groove 73 extends the entire width of cartridge 6'! so that the blank as a whole is held against rotatl n While spring 12 keeps the cartridge firmly seated against lip 62a atall times. The outer rim of )ipider 59 is provided with a number of pairs oi lugs 14 properly spaced to fit snugly against tM sides of cartridge 6?, thus holding the cartridge against any circumferential movement around the spider when contact is had with cutting tool l8. Lip 62a is preferably continuous so that cartridges 61 can be mounted in any relative position of the spider and ring 62.

A variational form of fitting for mounting a blank on the hub of spider 59 is illustrated in Fig. 10. This telescope-type fitting comprises an inner sleeve i5 attached to the spider hub by a threaded stud, and an outer sleeve 1'! which bears against compression spring 76 within sleeve 15. Since the outer sleeve has a diameter somewhat smaller than the diameter of the threat in blank 65, the outer sleeve is provided with a flared skirt 77a against which the end of the blank seats. The blank and cartridge are mounted by inserting sleeve 11 in the throat of the mouthpiece blank and compressing spring 16 suificiently to permit groove 13 of the cartridge to engage lip 62a as described above. Skirt Ha, being conical, centers the mouthpiece with respect to the fitting, and has the further advantage that it will accommodate-mouthpieces with any size of throat in the range between the minimum and maximum diameters of skirt Ha.

It is contemplated that in actual practice the mouthpiece blanks will be formed preliminarily to the approximate shape finally desired. This may be done by moulding the blanks, or by taking a roughing cut across the top of the blanks to form a preliminary face surface that gives approximately, say within a few thousandths of an inch, the final shape. Hence the blanks in the drawings are all shown as being ready for the final finishing cut.

After the blanks and cartridges are mounted in the drum, it may be desirable to adjust them with respect to the cutting tool. This is accomplished by first loosening lock screws 64. The spider 59 and. ring 62 may then be raised or lowered together relative to tool l8, carrying all the mounted blanks bodily up or down, by turning spider 59 on threaded flange 58a. Because of the threaded connection 60, the spider as it rotates moves vertically relative to the flange. In a similar manner the thread at 63 can be used to tilt the blanks, since by turning ring 62 on spider 59, the ring alone may be relatively raised or lowered and to raise or lower the outer ends of the blanks and their cartridges.

At the left-hand end of base I is bridge [2 by which template I4 is supported in place. Bridge l2 comprises a pair of spaced upright end posts 18, only one of these end posts being shown in Figs. 2 and as the other post is identical therewith. Carried by and between the top ends of posts 18 is cross bar 19 which has a 1ongitudinally extending slot 19a opening to the top side of the bar and having inclined side walls as shown in Fig. 5. Mounted to slide longitudinally within the slot 19a, is template clamp 80 in which template I4 is rigidly aflixed. Clamp 80 has at each end a vertical slot 80a that extends longitudinally of the clamp for at least a portion of its length, though it may extend throughout the entire length of the clamp, becoming a single slot, that is, the clamp is formed in two separate halves. At each end of the clamp is a lock screw Bl threaded into a tapered bore. After the template and clamp have been moved longitudinally of cross bar 19 to place them in the desired position, lock screws 8| are then tightened and as a consequence of the forward movement of the screws in their tapered bores, the bottom wedge-shaped portion of the clamp is expanded and grips the tapered sides of the cross-bar slot 79a.

To enable the operator to exactly locate the template, upon one side of clamp 80 is engraved an index 82 and cross-bar 19 is provided with scale means as shown in Fig. 2, the scale being preferably graduated in inches and decimal fractions thereof. The scale may be engraved directly upon the cross-bar or it may be upon a separable member attached thereto. In order to accurately aline template M with index 82, both the template and clamp are provided with alining holes, the holes 82a in clamp being placed exactly at index 82, and the hole in the template is preferably at the vertex of curved surface Mb. The template and index 82 are brought into precise registration by means of an alining pin (not shown) passing through these holes. This position of registration is then maintained by tightening clamp screws 83 which pass through the clamp and template, the template being a loose fit around screws 83.

It is desirable to utilize the open space beneath cross-bar 19 and between end posts 18 for storage of tools, loose parts, and any other suitable articles.

For this purpose .a pair of ciated scale means covers 84 are hinged at .85 to an end post 18, covers 84 being placed one on each side of crossbar 19 and adapted to swing outwardly. Each cover may be provided with shelves or other means for forming storage compartments.

The top surface of template I4 has a flat horizontal portion Ma. and a curved portion Mb, the latter bearing a definite mathematical relation to the curve which it is desired to impart to the cut face of the mouthpiece blank. It is in contact with this top surface of the template that follower l9 moves. In order to impart to cutting tool 18 the desired movement as determined by the motion of follower l9 over the template surface, follower I9 and tool l8 are interconnected by means of arm 11. As was described above, arm I! is pivoted at or near one end by pin 3| on cradle 30. The connection between arm I! and pivot pin 3| is here shown (Fig. 3) as including a pair of ball bearings within which pivot pin 3| is journaled and which are secured to arm H by means of a split circular shell Ila. The sides of shell l'la are contracted by means of bolts, not shown, to secure the bearings in place and pin 3| is shouldered as indicated so that the central portion of larger diameter prevents any sideways movement of arm I! along the pivot pin. The longitudina1 axis of arm I! is parallel to the direction of cradle movement and perpendicular to the pivot axis, so that the cradle supports the arm for longitudinal movement of translation while the pivot permits swinging movement in a vertical arc.

The other end of arm I! is attached to and supported by follower I9. The follower assembly includes rider 8'! which is, as shown in Fig. 5, of generally U-shaped cross-section having at its upper end a bore adapted to receive the round end of arm I! with sliding fit. Arm [1 is preferably provided with a rib along its lower side or other means to prevent rotation of the rider about the arm. Rotatably mounted in the two depending legs of rider 91 is roller l9 which is the follower that rolls over the top surface of template l4. It is preferred that follower [9 be a roller or similar member as shown in order to reduce friction as far as possible, but it is also within the scope of the invention to provide a fixed follower, such as a knife edge, which slides over the template surface. The sides of rider 81 extend below the template surface in order to stabilize the position of arm I! and prevent it from being knocked sideways off the template.

Arm I1 is also provided with scale means as shown, preferably graduated in inches and decimal fractions thereof, so that the exact position of follower I9 on the arm can be definitely determined. On one side of rider 8! is placed an indexing cross hair 89 in exact vertical registration with the center of follower l9, the scale being visible underneath cross hair 89 so that the follower position can be determined by the scale.

After rider 8'! has been moved along arm I1 to any selected position, it is held fixed in the adjusted position by tightening clamp screws 99. Although the positions of template l4 and follower l9 can be independently ascertained and adjusted by reference to their respective assosince both scales preferably have their zero point at the vertical axis of drum 2|, it is more convenient to set both parts at once. To permit this the template and rider 81 are provided with bores 9i and 9m respectively.

When these bores are brought into registration of curved surface and apin passed therethrough, the template and follower assemblies are locked together as one unit and movement between adjustedpositions will be exactly equal for both units. This procedure simplifies adjustment of the parts. vertical alinement with index 82 andthe vortex Mb, and bores 9 la are in vertical alinement with cross hair 89 so that whenthe template and follower assembliesare locked together, their indices are in vertical alinement.

At a position on arm 11 intermediate pivot 3| and follower I9 is placed cutting tool 3, although the scope of my invention includes placing the cutting tool and follower .on opposite sides of the pivot 3|, The tool-holding assembly is shown in detail in Fig. 4. This assembly comprises sleeve 93 externally threaded at 94 to fit within a threaded bore in arm I! and internally threaded at 95 to receive the threaded upper end of shank 96. Tool 18 is held within shank 96 by means of set screws 91. The upper or hit end of tool I8 is preferably square in cross-section or otherwise shaped so that it can be held firmly and accurately within shank 96 without rotating therein, set screws 91 thus being relied upon only to keep the cutting tool from moving longitudinally within the holding shank.

The lower end of shank 96 is provided with a V-shaped slot 96a along one side; and lock screw 98 threaded into arm IT has a sharp point engageable within slot 96a to keep shank 96 from rotating relative to the arm. At the same time vertical movement of the cutting tool is permitted since shank 95 can move longitudinally withinthe arm. Such vertical movement is required to allow adjustment of the cutting edge of the tool with respect to the blanks as they pass underneath the tool, and this movement is effected by turning sleeve 93. The outer and inner threads 94 and 95 on sleeve 93 are of different pitches so that the net movement of the cutting tool produced by each rotation of sleeve 93 is equal to the difference in pitch of the threads 94 and 95. Both threads are conventional right-hand threads and, in order that the cutting tool will move downwardly with right-hand rotation of sleeve 93, the inner thread is a finer one of smaller pitch than outer thread 94. After tool 18 has been adjusted to the proper height, sleeve 93 is locked against rotation by means of thumb screw 99, a block of wood or other relatively softer material being preferably interposed between the end of screw 99 and sleeve 93 as shown in Fig. 4 so that the sleeve threads will not be injured.

It will be realized that the cutting tool and the mounting therefor may take any one of a wide variety of forms. The mounting herein illustratedis preferred because it is readily adapted to commercially available tools of the type illuslustrated which have square bits; and also be-- cause the differential thread arrangement Yon sleeve 93 produces very small movement of the cutting tool for relatively large and easily ascertained movements of the adjusting sleeve 93. Obviously, the difference in pitches between threads 94 and 95 may be reduced to a very small value, so that any desired accuracy in the adjustment of the cutting tool can be obtained. Cutting tool I8 itself may be of any suitable material, as for example some commercial type of tool steel. However, greater accuracy and longer life-can be obtained with a-tool havinga cutting edge formed by a tip of some very hard substance, as for example a commercial tungsten f.

' from rack I I D.

carbide alloy. Consequently, a tool of this latter type is preferred.

Cutting fluid of a suitable nature is supplied to the forward cutting edge of a suitable nature is supplied to the forward cutting edge of tool It by nozzle IIII attached to the lower end of bore I02 extending vertically through arm IT. The cutting fluid is supplied to bore I02 by means of a flexible hose I 03 from a pump or other source, not shown. The cutting fluid runs down off the blanks through the open spaces between the spokes of spider 59 and then into pan I68 through a series of drain holes I 05 in shell 58. As shown in Fig. 3, pan IE6 is in the form of an annular trough supported on a number of posts IG'I (Fig. 3) resting at their lower ends on base Ill. The cutting fluid drains from. pan Hi6 through outlet hose I08 which preferably leads to a pump in order to provide continuous recirculation of the cutting fluid.

A depending annular flange is placed around the periphery of shell 58 as shown to keep the cutting fluid from splashing out of pan I66. In order to prevent the cutting fluid from working into the bearings for column 20, the rim of cap plate 26 has a depending flange and the hub of shell 20 has an upstanding flange, as seen in Figs. 3 and 6. are further sealed by providing a felt washer I59 that fills the space between cap plate 26 and the upper end of column 20.

As has been described above, arm I1 is mounted to move longitudinally. It will be apparent from Fig. 6 that the longitudinal movement of arm I! causes tool I8 to traverse the length of a mouthpiece blank 66 so that the successive materialremoving cuts taken as the blank is carried past the tool move gradually outwardly toward the tip of the blank to form the transversely flattened face desired. This traversing movement of the tool is controlled by a rack and pinion arrangement which causes the entire arm and its supports to move longitudinally, cradle 30 moving along rails 28 and follower I9 moving over the top surface of template I4.

On the top surface of each side cover 38 is mounted a rack III], and in engagement with each rack is a pinion III mounted upon a common shaft II2. Shaft H2 is driven by a motor and speed-reducing mechanism of any desired conventional design, the motor and speed reducer being carried on a frame H3 and enclosed within housing H4. The details of these pieces of apparatus are not shown since various types of mechanism commercially available may be used, but it is preferred to use mechanism. which will produce a speed of revolution of pinion III of the order of three or four revolutions per hour, since with the proportions shown it only requires approximately one revolution of pinion III for tool I8 to traverse the entire length of a blank 66.

Motor frame I I3 is mounted at its forward end to arm Il, preferably by means of a ball and socket joint at H5. This type of connection is preferred since it, together with the two pinions l I I, provides a three-point support for the weight of the motor and frame and allows suflicient freedom of movement around a horizontal axis that the weight is distributed equally upon the twopinions. A further advantage of this construction is that pinions I I I may be readily disengaged At the rear end of frame H3 is placed a lift II8 by which the frame may be grasped and raised to swing it about ball and The bearings within column 28' socket joint I I5. Thisis done when arm I! is to be'moved back, thatis; to the right as in Fig.6, to start another cut across one or more mouthpiece blanks 66; ,Motor frame I I3 is held against any lateral movement with respect to arm I1 and pinions II I are alined with respect to their respective racks by a pair of guide pins I I9 (Fig. 3) securedat'their lower ends to arm Il'. Suitably vsp'aced'bores are provided in lift II 8 which fit :over and engagepins H9 when the motor frame islowered to engage the pinions with the racks.-

Electric power is supplied through leads I2I (Fig. .1)" to the main drive motor 53 and through leads I22 to the motor within housingIHl. Because the electrical connections to these motors will be readily apparent to those skilled inthe art, no electrical wiring diagram is illustrated. It is. suficient thata manually operated switch be placed in each oftlie electric :lines HI and I22 in order to control separately the supply of current to the two motors. However, it is entirely within the scope of the invention to interconnect the two motorsor to makevarious other modifications in the electric circuit such as supplying automatic switches or relays for tripping the switches in order to prevent the cutting tool from overrunning.

It is "desirable, though not necessary, to have measuring means indicating the exact position of cutting tool I8 sothat the actual'curve out upon the mouthpiece willb indicated at all times during the cutting operation. For this purpose dial gauge I36 is attached to arm-l1 in such a waythat plunger I 3| of thegauge'rides over a'p'olished plane surface on the. top side of bar- I32. Bar I32 is pivotally mounted at I33 to the upstanding leg of angle bracket I34 which is in turn attached to the upper endof post I35- boltedat its lower end to base Iii. At each end of bar I32 is an adjusting screw I31 provided with-a lock nut I38, and by means of these two adjusting screws the upper surface ofbar I32 may be made accurately horizontal and parallel to the horizontal plane determined by rails 28;

Thepositicn of cutting tool I8 along the longitud'inal axis of arm i7 is indicated by pointer Hill-attached to arm I'I' andcooperating with fixed-scale II-attached to the lower leg of angle bracket I34. Scale MI may have its zero placed atanyconvenient point, and in cooperation with pointer I40 indicates at any time the horizontal position or movement of tool I8. "After'dial gauge I36 has- 'been'set to zero with bar I32 in an absolutely horizontal position, vertical movement of tool I8 with reference to the datum plane established by bar I32 is indicated by the dial gauge. Although dial gauge I 30 may read the actual movement of arm H at the gauge, it is more convenient to convert it to a direct reading instrument. This is easily done by locating the center of the gauge at exactly twice the distance from the pivot 3| that tool I8 is from pivot 3|. Then by recalibrating the scale on gauge I30 to half its absolute value, the readings on the dial in a single verticalplane passing through the axis of arm I! perpendicularly to the horizontal path. of rotation of drum 2| and the blanks carried thereby. The rotational movement of the drum carries one or more blanks 66 past cutting tool i8, and the relative movement of the blanks and tool removes materialfrom the blanks to produce the desired face on them; this drum movement may thus be termed a cut producing movement. The arm movement of translation is horizontal and determined by. the supports of arm ll, namely, cradl 30 and rider 81. Rails 28 confine cradle 30 and pivot 3| to movement only in a straight line. in a horizontal plane, while template surface I4a likewise confines initial movement of rider 8'! and follower [9 to horizontal movement parallel .to rails 28. The

top plane surface of bar I32 is adjusted to a horizontal position parallel to surfaces Ma, and 28, and'when in this position, dial I30 records no change as the arm moves along these guiding surfaces- In this way the alinement of these three parallel horizontal surfaces can be checked and it can be seen when the cutting edge of tool 18 is movingin a truly horizontal plane. This tr'anslatory movement of the cutting tool can be describedas a traversing movement since its purpose is to cause the cutting tool to traverse the length of a blank 66 so that cuts on the blanks are successive and closely spaced. Because of the rigid interconnection between tool I8 and follower'l9, th horizontal component'of the tool movement represented by this-translatory or traversing motion is at all times exactly equal to the horizontal component or translatory movement of the follower moving over the template.

While the movement of translation of arm IT and the parts attached thereto continues to take place as the arm moves the follower over the curved surface Mb of the template, the movement of the arm during this latter stage is no longer only one of translation since there now occursrotational movement of the arm about the axis of pivot3l. The curved surface [41) bears a definite mathematical relation to the curve'desired to be out on the mouthpiece blank,

as will be further explained, but it' will be seen that the curves of th template and the finished mouthpiece are not exact duplicates since the rotational movement of the cutting tool is less than the rotational movement of the follower as the former is closer to the center of rotation. The linearextent of this movement of the cutting tool and follower is determined by the distances 0. and b iFig. 2) by which these elements are removedfrom the axis of pivot 3|. Because these two lever arms are unequal in length, the tool movement will be a fixed fraction of the follower movement, the fraction being represented by the ratio a/b. Becausethe rotational movement of the cutting tool is of such small magnitude, it normally being of the order of two millimeters, it may be considered as simply the vertical component of the composit tool movement and as being perpendicular, or substantially so, to the horizontal component or traversing movement of the tool. Likewise, the rotational movement of follower i9 is described as being the vertical component of the follower movement.

I Although it is not necessary to observe such a "relation, it is decidedly advantageous that the axis of pivot 31, the cutting tip of tool [8, and a known point on the follower l9 lie in a commonhorizontal plane'as indicated in Fig. 2 at I50. Such a construction greatly simplifies the arrangement of the parts, eliminates compensations and corrections otherwise required, and

makes for greater accuracy in the final product. The follower point to be placed in plane I!) is a known point within the follower which it is desired to move over a predetermined path having a definite mathematical relation to the face curve to be produced on the mouthpiece blank. With a fixed follower, this point may be the point of contact of the followerwith the template, and in this case template surf-ace Ma lies also in plane I50; with a roller follower constructed as shown, the rotational axis of thefollower is the point placed in plane I50. In the first instance, the curved surface Mb coincides with the predetermined path of the follower point; in the latter instance, curve MI) is preferably compensated slightly to produce the identical movement of the follower axis that would be had with the point of a fixed follower, such compensation arising from the fact that the arcuate path of the follower axis and the template surface I 4b have a constantly changing vertical spacing between them and this change in the vertical distance between the template and the follower axis must be allowed for in producing the proper motion of the axis. Such compensation is preferred because with the roller follower, it is actually the curved path taken by the selected point on the follower that is reduced in vertical dimension to determine the shape of the mouthpiece curve,

rather than the curve of the template itself, although the latter is referred to in the following description since the template produces the physical guiding surface and the axis path bears a fixed relation thereto.

The vertex of curve Mb where it joins fiat Ma is alined vertically with index 82, and when the follower is directly above the template index, it is then ready to curve the mouthpiece face longitudinally upon added movement toward the left, that is, toward the tip of a blank as it passes under the cutting tool. Any movement of the template alone along the bridge has the effect of shifting bodily the location of the curve on the mouthpiece face by an equal distance, but the movement does not change the characteristic shape of the curve. The shape of the curve may be changed either by moving rider 8'! alone with reference to the template or by moving the rider and template together, since by either of these movements the distance b is changed so that the value of the ratio (1/1) is altered. The shape of the cut face, although changed, still bears a definite similarity to the face produced before such movement of the follower, as will chine, the distance b may be varied over a considerable range as has been explained. The result is that within the physical limits of the dimension D, an infinite number of curves all belonging to the same mathematical family may be cut on mouthpiece blanks from a single standard template by the simple procedure of moving the template and follower closer or farther from pivot 35.

The changesin shape of the face curves thus possible can be most easily described by analogy with the following example. Visualize a face curve formed using the distance b shown in the drawings, as being drawn upon a sheet of elastic material, such as rubber, held in a frame having rigid side pieces in such a manner that the sheet is placed under an initial tension along the Y axis alone, While there is no tension on the X axis. Moving the follower inwardly to shorten distance I) has the effect of increasing the ratio a/b so that the vertical component of tool movement and consequently the ordinates of the curve produced are increased. This is comparable to spreading farther apart the top and bottom sides of the frame holding the elastic sheet so that all dimensions of the imaginary curve along the Y axis are proportionately increased without changing dimensions along the X axis. llfovement of follower i8 outwardly on arm ll reverses the procedure and decreases the ratio a/b. The proportionate movement of tool it is then less and is comparable to allowing the top and bottom sides of the frame to come nearer one another, thus shrinking the ordimates of the imaginary curve on the elastic sheet without changing the value of the dimensions along the X axis. As far as the mouthpiece blank itself is concerned, the final result of these changes is that the opening between the tip of the mouthpiece and the reed in its neutral position is respectively increased or decreased by moving follower l9 inwardly to decrease the distance b or moving it outwardly to increase distance b. All curves within the range that can be cut thus on a mouthpiece from a single standard template are similar to each other and to the template in that they follow the same general mathematical formula, but differ from each other in that the coefiicients of the terms in the formula for the curve are changed progressively as the ratio a/b is changed.

Having described a preferred embodiment of my invention, it will be realized that changes in the design, arrangement, and location of parts may be made without departing from the scope of my invention; consequently it is to be understood that the foregoing description is to be considered as illustrative of, rather than limitative upon, the claims appended hereto.

I claim:

1. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; rotatable blank supporting means for mounting a blank in a predetermined position to engage the cutting tool; drive means rotating said supporting means to move the blank past the cutting edge of the tool to remove material from the blank and form a face thereon; cooperating template and follower means adapted to produce movement of a point within the follower over a path bearing a mathematical relation to the contour desired for the mouthpiece face; and rigid means interconnecting said follower and cutting tool so arranged that one component of the cutting edge movement is equal to the corresponding compo nent of movement of said follower point and the other component of the cutting edge movement at right angles to the first-mentioned component is a predetermined fixed fraction of the corresponding other component of movement of said follower point.

2. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; rotatable blank supporting means for mounting a blank in a predetermined position to engage the cutting tool; drive means rotating said supporting means to move the blank past the cutting edge of the tool to remove material from the blank and form a face thereon; cooperating template and follower means adapted to produce move- 10 ment of a point within the follower over a path bearing a mathematical relation to the contour desired for the mouthpiece face; and a rigid arm rigidly interconnecting the follower and the cutting tool, said arm having a pivotal mounting on a support capable of linear movement only and carrying the tool at a fixed position closer to the pivotal mounting than the follower is to the pivotal mounting, all so arranged that one component of movement of said follower point moves the arm longitudinally and produces a similar and equal'component of movement of the cutting edge and the other component of movement of said follower point at right angles to the first-mentioned component produces a similar component of movement of the cutting edge proportional to the ratio between the fixed distances of the tool and the follower from the arm pivot.

3. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; rotatable blank supporting means for mounting a blank in a radial position thereon to engage the tool; drive means rotating said supporting means to move the whole blank intermittently past the cutting edge of the tool to remove material from s the blank and form a face thereon; a fixed template having -a curved surface bearing a mathematical relation to the curve desired for the mouthpiece face; a follower movable linearly over the template surface; and a rigid member imparting to the tool movement governed by the movement of the follower over the template surface.

4. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; a rotatable drum mounting a plurality of blanks in radial positions thereon to engage the tool; drive means rotating the drum to move the blanks successively past the cutting edge of the tool to remove material from the blanks and form similar faces thereon; a fixed template having a curved surface bearing a mathematical relation to the curve desired for each mouthpiece face; a follower movable linearly over the template surface; and a rigid member imparting to the tool movement governed by the movement of the follower over the template surface.

5. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the

combination of a tool having a cutting edge; ro-

tatable blank supporting means for mounting a blank in a predetermined position to engage the cutting tool; drive means rotating said supporting means to move the blank past the cutting edge of the tool to remove material from the blank and form a face thereon; a template having a curved surface bearing a mathematical relation to the curve desired for the mouthpiece face; a follower movable over the template surface; a member imparting to the tool movement governed by the movement of the follower over the template surface; and, an indicating gauge secured to the last-mentioned member indicatdatum plane.

ing the movementof said member from a fixed base; a pair of rails secured to the post; acradle mounted to .move along and be guided by-the rails; an arm pivotally mounted on the cradle; a template having a curved surface having a mathematical relation to the curve desired for the mouthpiece face; a follower attached to the arm and riding over the template; a cutting tool carried by the arm; a column rotatably mounted on the base and concentric with the post; a blank support on the column for supporting a blank in position for engagement with the tool; drive means to rotate the column and blank support; and means to move the arm and cradle along the rails radially of the blank support.

'7. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; a rotatable drum mounting a plurality of blanks in position to engage the tool, said drum comprising a rotatably mounted shell, a spider adjustably mounted on the shell to rotate therewith, a ring adjustably mounted on the spider, locking means on the ring engaging the shellto hold the spider and ring against movement relative thereto, fittings on the spider adapted to support one end of a blank, and fittings on the ring adapted to support the opposite end of a blank in a position radially of the drum; drive means rotating the drum to move the blanks successively past the cutting edge of the tool to remove material from the blanks and form similar faces thereon; a

template having a curved surface bearing a mathematical relation to the curve desired for each mouthpiece face; a follower movable over the template surface; and a member imparting to the tool movement governed by the movement of the follower over the template surface.

8. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; rotatable means for mounting a blank in position to engage the tool; said rotatable means comprising a rotatably mounted shell, a spider adjustably mounted on the shell to rotate therewith, a ring adjustably mounted on the spider, locking means on the ring engaging the shell to hold the spider and ring against movement relative thereto, a cartridge enclosing a portion of the mouthpiece blank and open for its entire length for a portion of its circumference, cementing means around a portion of the mouthpiece blank engaging the cartridge to hold the blank firmly against rotational movement within the cartridge, fittings on the spider adapted to support one end of the blank, and fittings on the ring adapted to support the opposite end of the blank; drive means rotating the blank mounting means to move the blank past the cutting edge of the tool to form a face thereon; a template having a curved surface bearing a mathematical relation to the curve desired for said mouthpiece face; a

follower movable over the template surface; and a member imparting to the tool movement governed by the movement ofthe follower over the template surface.

9. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; a rotatable drum mounting a plurality of blanks in position-toengage thetool, said drum comprising a rotatably mounted shell, a spider adjustably mounted on the shell to rotatetherewith, a ring ,adjustably mounted on the spider, locking :means on the ring-engaging the shell to hold thespider and ,ring against movement relative thereto, a plurality of cartridges each enclosing a portion of a mouthpiece blank and .open for ,its .entire length fora portion of itscircumference,cement- .ing means inieach'cartridige around a portioniof the enclosed mouthpiece blank engaging the cartridge to hold the blank firmly against rotational movement within the cartridge, fittings on the spider adapted to engage the outer ends of each blank, and fittings on the ring adapted to engage the inner ends of each cartridge to mount the blanksin positions radial of the drum; drive means rotating the drum to move the blanks successively past the cutting edge of the tool to remove material from the blanks and form similar faces thereon; a template having a curved surface bearing a mathematical relation to the curve desired for each mouthpiece face; a follower movable over the template surface; and a member imparting to the tool movement governed by the movement of the follower over the template surface.

10. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; a rotatable blank support mounting the blank to engage intermittently the cutting tool and moving the blank past the tool in a circular path having its center outside the blank; a template having a curved surface bearing a mathematical relation to the curve desired for the mouthpiece face; a followed movable over the template surface; a rigid armextending radially of the blank support and mounted for longitudinal movement, the follower and cutting tool being mounted on said arm at fixed positions relative to each other, said arm imparting to the tool movement over a curved path; and drive means for rotating the blank support and for moving the arm.

11. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the

- combination of a tool having a cutting edge; a

relation to the curve desired for the mouthpiece 1 face; a follower movable over the template surface; a rigid arm extending radially of the blank support, the follower being attached to the arm near one end and the cutting tool being attached to the arm intermediate the ends at positions fixed with respect to each other; a traveling pivot supporting the other end of the arm at a fixed point on the arm. and capable with the arm of linear movement longitudinally of the arm to move the follower over the template, said arm imparting to the tool movement over a curved path; and drive means for rotating the blank supportand for movingthe arm.

12. In a machine for cutting faces on blanks to form mouthpieces for musical instruments, the combination of a tool having a cutting edge; blank supporting means rotatable about a vertical axis and holding a blank with the longitudinal axis of the blank substantially horizontal and radial of the supporting'means; drive means rotating the blank supporting means to move the 10 movement of the blank and the longitudinal axis of the blank to curve the mouthpiece face; means including said follower supporting the arm near each end for longitudinal linear movement and vertical pivotal movement about a pivot fixed with respect to the follower and cutting tool; and means moving the arm longitudinally to move the tool longitudinally of the blank and to move the follower over the template.

lI-IAJftl-t-Y H. CANTERBURY. 10

CERTIFICATE OF CORRECTION. Patent No. 2,225,15h. December 17, 191m.

HARRY H. CANTERBURY. It is hereby certified that error appears inthe printed specification of the above numbered patent requiring correction as follows: Page 1, second column, line 15, for the word "longitudinally" rea'd --longitudinal--; page 2, first column, line 21, for "postiion" read -position--; line 55; for "November" read -December--; page 5, second column, line 6, for "vortex" read -vertex; page 6, first column, lineslp and 5, strike out "of a suit-.

able nature is supplied to the forward cutting edge"; and that the said Letters Patentshould be read with this correction therein that the same may conform to the record of the case in the Patent Office. I Signed and sealed this 11th day of February, A. D. 19in.

Henry Van Arsdale, (qann Acting Commissioner of Patents. 

